Pregnant women are rigorously counseled to avoid any drugs, diagnostic tests, or treatments that might impact the developing embryo or fetus. Most women reflexively fear the idea of vaccination in pregnancy, although vaccination for many diseases presents no problems in pregnancy. The Centers for Disease Control and physicians are very concerned that pregnant women will refuse vaccination, with potentially lethal results.
How should pregnant women decide what to do? The best place to start is with what we know for sure. We have a great deal of evidence that H1N1 influenza is particularly lethal in pregnant women. To put it in perspective, the chance of a pregnant woman dying from H1N1 is greater than the chance of a heart patient dying during triple bypass surgery. That is not a trivial risk.
We have no evidence that the vaccine will cause any harm to pregnant women or their unborn children beyond the side effects associated with other flu vaccines, such as local irritation at the vaccine site, or the rare complication of Gullain Barre Syndrome. We have no reason to expect that the H1N1 vaccine will be any different.
It would be much easier to make the decision if we knew more, if we had some idea of how extensive the fall outbreak will be, if we had longer experience with the specific vaccine. Unfortunately, that information is not available to us and by the time it becomes available may more pregnant women may sicken and die unnecessarily.
Given the dramatic threat and the fact that we know of no unusual complications of vaccination, the decision seems clear. Every pregnant woman should get vaccinated as soon as possible.